The invention relates to a yarn processing system having a group of functionally interrelated components including a yarn consuming textile machine and to a method of operating the yarn processing system.
Already known computerised yarn processing systems, such as a weaving machine with its associated feeding and accessory components, are equipped with complex multi-line wiring for transmitting signals between interconnected operation elements and to associated control and/or monitoring means. Said wiring extends between all components of the component group of the yarn processing system.
Each of EP-A-0 458 874 and WO 92/03881 A discloses a method and structural means for controlling and/or monitoring a yarn processing system with the help of a two-line field bus for the transmission of messages in the form of a quick communication protocol with information types differing in their respective priorities in order to achieve real-time transmission at least for highest priority information using the same field bus as lower priority information types. The wiring thus can be simplified by the two-line field bus and, due to the communication protocol of special communication microprocessors, at the interfaces with the field bus. However, in order to connect all transmission participants to the field bus, the field bus has to be integrated in the crowded environment of the yarn processing system at locations where mounting space and access are severely restricted. The field bus is vulnerable to damage. The entire system has to have a complicated layout configuration. Damage to the field bus easily causes breakdowns of the communication microprocessors.
WO 98/50833 discloses an automated residence management system using radio frequency communication between sub-systems and appliances remotely located in a plurality of residences and other spaces to operate in a centrally controlled manner, e.g. in private homes, apartment buildings, office buildings, and other occupied spaces and structures. Radio transmission takes place with a variable transmission/reception frequency such that the current and variable frequencies hop between two or more frequencies in synchronisation. A spread spectrum communication technique in the 900 MHz transmission range is recommended. Typical examples of such sub-systems are water heaters, lights, security systems, internal telephone wiring systems, gas meter, electric meter, water meter, hot tubes, clothes dryer, etc.
It is a task of the invention to provide a more reliable and flexible computerised yarn processing system as well as provide a method to operate and control said yarn processing system in a more reliable and flexible fashion.
Said task is achieved by providing a communication microprocessor in each electronic control and/or monitoring means of a yarn processing system wherein the microprocessor is connected to a radio transmitter/receiver for data transmissions between components. The method of operating this system includes generating control and/or monitoring data and converting this data into radio signals which are transmitted and received by the radio transmitter/receiver.
Radio transmissions within a frequency band, such as that available for industrial applications and via wireless transmission paths, avoid the necessity of designing a complicated field bus layout configuration. The transmission participants are communicating with each other by radio transmissions. This leads to a comfortable modular interchangeability of the transmission participants. In case of transmission failures or disturbances, the danger of damages for other transmission participants is reduced. Each component or a component group can easily be pre-fabricated independently from others and by other manufacturers. The necessary compatibility is easy to be achieved and allows an advantageous modular composition of different yarn processing systems based upon standardizable base components. In one and the same yarn processing system, a radio transmission system or several separate systems can be provided using a common frequency in the 2.4 GHz or 400 MHz band. Since in a radio transmission system all participants are able to listen to or output information without the restriction of a structural field bus as in prior art, particular care is necessary for the reliability of the respective information to be transmitted or received. This radio specific task is fulfilled by the radio media access control interface means responsible for the organisation and conversion of the information into the radio signals, as well as the evaluation of the incoming radio signals. Modern radio transmitters/receivers for industrial applications with a reach of about 10 meters as well as said radio media access control interface means are available for a fair price and with reliable operational behaviour and are easy to be integrated in existing electronic control and/or monitoring means. Even though said radio media access control interface means constitute additional administrative overhead equipment in the system, the most important advantage is the avoidance of structural field bus wiring while still taking advantage of a quick and reliable communication protocol.
In a further embodiment even, further active yarn processing accessory components are integrated in the radio transmission system for control and/or monitoring purposes. A pre-requisite for said accessory components is an electronic control and/or monitoring means, a power supply, a communication microprocessor and the radio media access control interface means for its radio transmitter/receiver. Also in said accessory components of the yarn processing system sensors, yarn brakes, yarn clamps, tensiometers, yarn cutters, yarn selectors, yarn conveyors, etc., will receive or output ratio transmitted data.
It is advantageous to use radio transmitters/receivers according to TDMA-standards i.e. a form of radio transmissions as used by GSM-mobile telephone systems. Alternatively, radio transmitters/receivers can be used according to the CDMA-standards which is a more sophisticated form of radio transmissions with increased reliability and high disturbance safety level.
Said radio media access control interface means could be constituted by software only in said communication microprocessor or in an associated microprocessor.
The communication microprocessor may be customised and apt to configure said different information types each with a frame having frame fields containing data. Said frame configuration is an ideal measure for quick and fail-safe serial or serial and digital transmission. By configuring said frames with at least one data frame field containing general prioritising data and/or individual addressing data, a real-time transmission for important information can be achieved when necessary for a real-time control and/or monitoring of a yarn processing system, or to transmit or receive information between particular selected participants in the transmission system only.
The high reliability and disturbance free radio transmission level in a yarn processing system could advantageously be further extended by using a hand-held controller for transmission and/or receipt of information in a wireless fashion or to form selected or not selected participants in the transmission system. Expediently said hand-held controller is used to set operation parameters or readout stored information. It can easily be equipped such that it is compatible with several yarn processing systems of similar or different kinds.
Participants in the transmission system are not only the yarn feeding devices and the textile machine itself but advantageously yarn sensor elements, drive means, drive operating means, tensiometers, yarn brakes, threading equipment, parameter setting and storing elements, etc., all of which are prepared to output or respond to data transmitted by the respective radio transmitters/receivers.